1. Field of the Invention
The present disclosure relates in general to valves and more particularly, to filters of gate valves for use with oil, gas and other fluids.
2. Description of Prior Art
A gate valve has a body with a flow passage extending through it. A gate cavity intersects the flow passage, and seat rings are located at the upstream and downstream points of intersection. Seat ring seals are located between the seat rings and the valve body. An actuator, which may be mechanical, hydraulic or electrical moves a gate within the cavity between open and closed positions. The gate has an aperture through it. When in the open position, the aperture registers with the flow passage. In the closed position, a seal surface on the gate contacts the downstream seat ring. The upstream pressure exerts a force pushing the seal surface into tight sealing engagement.
When operating the valve, debris often enters the valve and accumulates. The debris can sometimes pass into the space between the seat rings and the valve body and accumulate. Debris can also pass between the seat rings and the gate to enter the gate cavity. The debris causes damage to components in the body and clogs the cavity, preventing proper operation of the valve. This debris can also wear on the seat ring seals damaging these seals and causing them to fail.